In your Kickserv Quickbooks page the error should be there under the error tab. In that error the customer name or customer number should be there pointing you to the customer record. Typically, the problem is that the parent record name is already in your QBOE account and Kickserv is attempting to sync the parent and it's child record to QBOE.
If this parent record is truly independent and unrelated to the same named customer in QBOE then you need to decide how to differentiate their names.
Add a middle initial
put a number at the end of the name
add the street address to the name
The two customer records are to be the same customer
Now, if the two records are suppose to be the same record, but the record in QBOE was put there manually then what you need to do is the following:
Renaming the records
Remove the invoice from the Ready To Sync queue. We don't want this invoice to sync just yet.
Use the Kickserv smart search feature and type C:#### in the search box. That is C for customer record, then a colon, then the customer number in the error message.
In KSA add a big "X" to the front of the parent customer name.
Sync'ing them both to KSA
Navigate back to your QBOE account and do some minor update to the customer record in question.
Come back to KSA and run the major global sync button
Once the sync is done check for any other sync errors that may have risen and handle them successfully. Run the sync again til there are no more errors to handle.
Now you should have both customer records in your KSA account. The one from QBOE will have the green QB symbol next to its name and the KSA originated customer record will have a big "X" in front of it.
Merge X customer into the other
Now, starting with the "X" customer record
Click the dropdown for editing the customer and select merge
In the new merge contact page type the parent record's name (i.e. Big Duplicating Co.).
Ensure you have the correct winning parent record before proceeding there is no undoing this process.
Press the green button [Merge contacts] and click OK.
Now, you can put the invoice for this customer back into the Ready To Sync queue and sync.
It should be that easy!